SLC-off GapFilled_Jun09.ppt

8/9/2019 SLC-off GapFilled_Jun09.ppt

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Remote Sensing Basics | June 14-20, 2009

SLC-Off Gap FilledProduct Generation

Richard IrishSSAI, NASA’s Goddard Space Flight Center

Richardirish!nasago"

Pat Scara#u$$a

SAIC, Center for Earth Observations and Science (EROS)

mailto:[email protected]:[email protected]


2/18


Scan Line Corrector Failure

On May 31, 2003, Landsat 7 e!erienced an ano"a#y ca$sin% the

Scan Line Corrector (SLC) to sto! f$nctionin% nor"a##y&

'he te#esco!e foc$ses ener%y onto a !air of "otion co"!ensation

"irrors (i&e& SLC) here it is redirected to the foca# !#anes and

acco$nts for the co"!o$nd effect of a#on%trac* orbita# "otion and

crosstrac* scannin% hich #eads to si%nificant over#a! and $nder#a!

in %ro$nd covera%e beteen s$ccessive scans&

+hi#e "issin% data is #ost, it as !ossib#e to "odify eistin%

a#%orith"s to !rod$ce i"a%ery containin% ro$%h#y 0- of thee!ected scene&

'he !rocessed !ostano"a#y data contin$es to "aintain its

e!ected radio"etric and %eo"etric fide#ity&


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Scan Line Corrector


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SLC-off Archi"e Potential

Landsat . has o$t#ived its desi%n #ife by an asto$ndin% 22years yet its de"ise i## #i*e#y !recede that of Landsat 7&

Over //0,000 SLCoff scenes have been ac$ired, archived,

and are avai#ab#e for free& Many $ni$e#y re!resent the on#y

recent Landsat observations over forei%n soi#&

'he %oa# of the a#%orith" !resented here is to ta! the va#$e

re!resented by the SLCoff archive by fi##in% "issin% !ie#s

ith radio"etry that has scientific !$r!ose&

+ith a LCM (Landsat ) sched$#ed for a #ate 2012 #a$nch,there "aybe no choice&


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Algorith# %escription

Step & - Scene Refra#ing 'refra#e(l&tpro)

Step * - Gap Filling 'gap(fillpro)

#tho$%h, the standard E'M L1' !rod$ct is %eo#ocated and

Orthonor"a#i4ed, scenes for co""on !ath5ros are not

necessari#y a#i%ned& Scene refra"in% ($sin% the 6eo'88 header)

estab#ishes a co""on fra"e and achieves re%istration thro$%h

trans#ation&

Co""on nei%horhood !ie#s (non4ero) are identified for each

!ri"ary scene !ie# %a! and its fi## scenes co$nter!arts&

Linear #easts$ares re%ression ana#ysis, $sin% 199 data

!oints yie#ds the !redictive e$ation $sed for fi##in%&


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Adapti"e +indo Logic

(x,y) (x,y) (x,y)

(x,y) (x,y) (x,y)

nchor scene 8i## scene 1 Co""on !ie#s : 9

nchor scene 8i## scene 1 Co""on !ie#s : 12

: %a! : va#id data


7/18Remote Sensing Basics | June 14-20, 2009

Predicter Relationship %e"eloped



Fra#e(and(fill

'he !ri"ary %oa# of this endeavor as to create freeare so anyone

ith a desire co$#d ta*e %reater advanta%e of the E'M SLCoff archive&

;nfot$nate#y, refra"e#ans are to

"a*e additiona# versions for Mac nt (32, /9 bit), +indos/9, Lin$

and So#aris (32 and /9 bit)&

htt!?55#andsathandboo*&%sfc&nasa&%ov5handboo*5softare5%a!



Fra#e(and(fill %ata Staging Rules

The primary scene to be filled is termed the anchor scene. It

MUST reside in a folder named anchor for the software to work.

The filler scenes reside in separate folders at the same directory

level as the anchor folder.

They are so named fill_scene_1, fill_scene_2... to reflect their

processing priority.

These folder naming conventions must be followed for the

software to work.



Fra#e(and(fill Opening +indo

@ote? 8ra"e



Refra#e(L& Para#eters



Gap Fill Para#eters



8ra"e



>ath 10, Ro .2 ac$ired on 152050 in +estern @i%eria&

./0 Su1-scene Anchor



./0 Fill Su1-Scene 2&




./0 Fill Su1-Scene 2*




./0 Filled Su1-Scene



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SLC-off Scene Selection Criteria

f !ossib#e, fi## scenes sho$#d be c#o$dfree ith "ini"a# chan%es

n scene content (e&%& sno)&

Choose fi## scenes that are te"!ora##y c#ose to the anchor to "ini"i4e

chan%in% %ro$nd cover& second choice o$#d be anniversary scenes

here scene content is si"i#ar&

Se#ect fi## scenes that are ithin 9 +RS cyc#es of the anchor& 'he

E'M scan cyc#e chan%es s#o#y over ti"e "eanin% the re#ative scan

%a! !hase i## vary across the scene if the ac$isition date interva#

s too %reat& +hat a!!ears to be a !erfect "atch "ay not be&

One "i%ht consider $sin% an SLCon scene as the fina# fi##

co"!onent& 'his i## ens$re co"!#ete %a! covera%e&

Documents

SLC-off GapFilled_Jun09.ppt